Trump said Monday that the United States would once again block ships belonging to the Islamic Republic or serving its customers from entering or leaving Iranian ports, while keeping the Strait of Hormuz open to traffic bound for other countries.

US Central Command said the blockade would take effect at 4 p.m. ET on Tuesday and apply to vessels traveling to or from Iranian ports and coastal areas. American forces would continue supporting ships in regional waters that were not violating the restrictions, CENTCOM added.

The US Navy-led Joint Maritime Information Center said the measure would cover Iran’s entire coastline, including ports and oil terminals. Neutral vessels traveling through Hormuz to non-Iranian destinations would be allowed to pass, while humanitarian shipments would be permitted after inspection.

The announcement came days after Trump informed congressional leaders that “military action commenced on July 7 against the government of the Islamic Republic.”

In his July 10 letter which was released on Monday, Trump said US forces launched “defensive strikes” after Iranian forces attacked several neutral-flagged commercial vessels in the Strait of Hormuz. The targets included missile launch sites, air defenses, maritime military assets, military-support infrastructure and command-and-control capabilities.

Trump said no American ground forces were involved and described the attacks as limited and measured. He nevertheless said US forces remained positioned to carry out further action, indicating that the July 7 operation marked the resumption of a military campaign rather than an isolated retaliatory strike.

The notification could further intensify a dispute between the White House and Congress over Trump’s authority to continue the war without legislative approval. Both chambers have voted to direct him to end the fighting or seek congressional authorization, while the administration says the president is acting within his constitutional powers as commander in chief.

US strikes have continued since the renewed campaign began. CENTCOM said American forces used one-way attack surface drones in combat for the first time on Sunday, striking a submarine and ship-maintenance facility at the Bandar Abbas Naval Base.

Three Corsair unmanned vessels hit the facility and degraded the Islamic Republic’s ability to attack commercial shipping, according to the US military.

Explosions in southern Iran

Fresh explosions were reported Monay across southern and southeastern Iran, within a coastal zone highlighted by CENTCOM.

A map released by US Central Command highlights a broad stretch of Iran’s southern coastline along the Persian Gulf and Gulf of Oman, hinting at the general range of ongoing US strikes.

The state-run Islamic Republic News Agency said the sound of four missile impacts was heard near Konarak, with the blasts also audible in Chabahar and Dashtiari.

The IRGC-affiliated Tasnim News Agency reported six loud explosions in Chabahar and Konarak and said areas around Chabahar had been targeted by the US military in recent nights. It also reported explosions and the activation of air defenses in Bandar Abbas.

Iran’s state broadcaster later denied that explosions had occurred in Bandar Abbas, Larak and several other southern locations, contradicting earlier reports by IRNA and Tasnim. No immediate casualty figures were announced.

The confrontation also continued at sea, with Tasnim reporting that several vessels accused of violating Iranian restrictions had been targeted in the Strait of Hormuz.

Iran’s armed forces warned they would respond forcefully to US interference with shipping and said regional governments providing logistical support to Washington could be regarded as participants in the war.

Trump, meanwhile, declared the United States the “Guardian of the Hormuz Strait” and proposed charging the equivalent of 20% of cargo shipped through the waterway, a plan rejected by the UN’s shipping agency as lacking a legal basis.

Trump also said the United States would hit Iran hard on Monday night and Tuesday, in an interview with conservative radio host Hugh Hewitt.

Asked about the memorandum of understanding, Trump said it had been a test for Iran and that Tehran had failed to honor it.